Research InterestsI have the following major research areas:
I. Diffusion tensor imaging (an MR technique that measures rate and direction of microscopic water motion) to examine white matter pathways in the brain. This technique is used by many investigators in an attempt to understand white matter microstructure. My recent work has centered on the histological correlation of DTI metrics. In addition, because DTI metrics can vary substantially within a single scanner at multiple time points as well as between scanners, my work is focused on understanding causes of such variability and designing methods to decrease it.
Since 1998, I have mentored third-year students at Duke University School of Medicine (typically one medical student per year) in both DTI research and perfusion imaging research. Although the research techniques are highly advanced, our implementation of various "user-friendly" software programs allows students with little or no prior experience to analyze data in a productive manner. Our research is also well-suited to individuals with advanced computer skills or an interest in biomedical or electrical engineering. Students work closely with research personnel on a daily basis. They also meet with collaborators from various basic science and clinical departments and me in a laboratory meeting once a week. The focus of these meetings is to plan experiments, refine research methods, discuss experimental results and prepare manuscripts. Students serve as first authors or co-authors on manuscripts based on their specific research project. The results of a number of such projects have been published.

II. Applications of nanotechnology to treatment of cancer (both CNS and non-CNS) and brain disorders. My research involves design and implementation of nanoparticles and fluorescent molecules for cancer diagnosis and therapy. Although I am trained as a neurologist and neuroradiologist, most of my nanotechnology-based research is oriented towards non-CNS tumors such as breast cancer and sarcomas. In the past few years, my Emory and Georgia Tech colleagues and I have conducted research using animals with naturally-occurring tumors at the University of Georgia College of Veterinary Medicine. This work has focused on the use of a handheld device to detect fluorophores that are administered intravenously prior to surgery. We are presently validating the use of this combination of imaging device and contrast agent to guide surgical resection of tumors. I am also interested in development of nanotechnology-based non-invasive and minimally invasive devices that can continuously monitor tumor physiological characteristics and response to therapy. This work is done in conjunction with a number of colleagues in Biomedical Engineering at both Duke and Emory and supported by a number of NIH grants. Finally, I have a strong interest in use of nanotechnology for tissue engineering and regenerative medicine.